Operating Instructions1. Users shall select types of quick couplings appropriately according to operating requirements and features of joints (including work pressure, medium properties, and flow, temperature, corrosiveness and ambient temperature, quantities and connecting types of pipes etc.)2. Users shall pay attention as followed if one end is connected by directly welding to hard hoses: 2.1 Remove the rubber sealing ring out of plug bushing by using of special hook. After the welding is finished and joints are completely cool down, mount the sealing ring into the plug bushing. 2.2 If a special hook is not available, other alternative methods can be adopted: plug the inner diameter side of the sealing ring inside the plug bushing with wet cloth or cotton yarn, to prevent the sealing property from high temperature welding damage. 2.3 Quick couplings shall not be placed on conductors such as metal plate, to prevent the inner part being burned by interrupt circuit that will affect the sealing property and matching precision at last. 3. Take cares on spherical surface (male quick coupling) and conical surface (female quick coupling) of ball joint during the process of usage and transportation, which shall not be scratched or crashed, in avoid of properties of connecting and sealing. 4. Two important factors to improve the service life are to select types of quick coupling correctly, and then make reasonable installation.